HCM, or hypertrophic cardiomyopathy, is a confusing and frustrating disease to understand. Stated basically, it is a common heart disease found in cats of all breeds and backgrounds where the left ventricle becomes enlarged. Cats can appear healthy (asymptomatic) or they can show signs of the disease which require an echocardiogram to give an accurate diagnosis. The difficult part of this disease is that there is no genetic test available to determine if a cat is a carrier. So a breeder, such as myself, scans their cats every year to monitor their cat’s heart. Maybe the scan is normal for the first two scans – so we keep using that cat in our breeding program, believing they are negative for HCM. Then suddenly the third scan shows signs of HCM. We have inadvertently “passed” HCM on to another generation of offspring without knowing it. My point is this – just because an adult cat is scanning negative for HCM does not guarantee the cat will never develop HCM in its lifetime, or that its kittens will not develop the disease. These are living creatures, and just like people, there is no “lifetime guarantee”.

At a recent visit with my cat’s cardiologist, I was able to ask a few questions about HCM I felt were important to clarify. Below are his answers and opinions:

How common is HCM in Sphynx versus other cats?

About average. He sees just as many house cats with HCM as Sphynx, or any other breed for that matter. Generally owners only bring sick cats, or cats referred by their veterinarian for suspected heart issues.

What are the visible signs of HCM?

Increased breathing, fatigue and paralysis.

What age should I test my cat for HCM?

You should test the cat right away if a cardiac problem is suspected. Otherwise if you decide to test, a good age to start would be 2-3 years old. Most HCM positive scans this particular cardiologist sees are in cats over 7 years of age.

How often should I test my cat that is in a breeding program?
Test the cat at 2-3 yrs old. If no signs of HCM are noted, test again every other year. Scanning annually is also an option.

Once diagnosis of HCM is made, what is the life expectancy of the cat?

It depends on the severity and age of the cat. Some cats can live for many years after their diagnosis and others aren’t as lucky.

The article below explains HCM in detail and is generally accepted by the veterinary community to be the most up to date information on this disease.

Feline Hypertrophic Cardiomyopathy:

What is hypertrophic cardiomyopathy?

Hypertrophic cardiomyopathy (HCM) is the most common heart disease of cats, whether they are random bred or pedigreed. It is a heart muscle disease in which the papillary muscles (the muscles in the left ventricle that anchor the mitral valve) and the walls of the left ventricle become abnormally thickened. HCM is often a progressive disease, and a proportion of affected cats develop heart failure if the muscle hypertrophy and subsequent scarring of the heart muscle significantly affects heart function. Cats with the disease may die suddenly and may develop a blood clot in the chamber above the left ventricle (i.e., the left atrium) that often then gets carried into the systemic arterial system, most commonly lodging in the terminal aorta, stopping blood flow to the rear legs.

What causes HCM in cats?

This is currently unknown in most cats although familial (hereditary) HCM has been observed in several breeds, such as the Maine Coon and American Shorthair. Anecdotal information suggests there is familial HCM in many other breeds. Heart muscle hypertrophy in cats can be caused by other diseases, such as systemic hypertension (high blood pressure) and hyperthyroidism. HCM is a primary disease of the heart muscle. Hypertension and hyperthyroidism cause secondary thickening of the left ventricle and so are not causes of HCM (although it is possible that they may exacerbate the disease if they become present in a cat with mild to moderate HCM). HCM is diagnosed when these other causes are ruled out.

Is HCM genetic?

In Maine Coons and American Shorthairs, HCM has been confirmed as an autosomal dominant inherited trait, as it is in humans where over 200 gene mutations in 10 genes have been found to cause the disease. The disease has variable expression; meaning some cats are severely affected, others are only mildly to moderately affected, and some cats may not have evidence of the disease yet produce affected offspring.

Recently, a mutation in the cardiac myosin binding protein C (cMyBP-C) gene causing HCM in the Maine Coon cat has been identified. Undoubtedly, other mutations responsible for HCM in cats remain to be discovered. However, since few veterinary cardiologists and geneticists have the expertise to study genes, it may be some time before the responsible gene or genes for each affected breed will be found. The mutation identified as a cause of HCM in Maine Coon cats may not be the same mutation or even on the same gene in other breeds. The genetics of HCM in each breed will require investigation of each individual breed.

Can HCM have a nutritional cause?

There is no evidence in cats, humans or other species of animals that HCM can have a nutritional cause.

How is HCM diagnosed?

HCM is diagnosed using ultrasound of the heart – an echocardiogram. Echocardiography is a good way to detect moderate to severely affected cats. However, it may not always detect mildly affected cats where changes in the heart can be minimal. Ideally, an echocardiogram to test cats for HCM should be performed by a board-certified cardiologist or radiologist.

In addition to an echocardiogram, other tests may also be useful in assessing cats with HCM. For example, a chest x-ray is necessary to detect heart failure in cats with severe HCM. An electrocardiogram is useful in cats that have abnormal heart rhythms. Blood pressure measurement and blood testing for hyperthyroidism are indicated to rule out other diseases that mimic HCM, especially mild to moderate HCM.

A genetic test is now available for the known cMyBP-C mutation causing HCM in Maine Coon cats. The test is available from the Veterinary Cardiac Genetics Lab of Dr. Kathryn Meurs at the College of Veterinary Medicine, Washington State University (http://www.vetmed.wsu.edu/deptsvcgl/). The test can identify which cats have the mutation. If a cat is identified as having the mutation, the test can also determine whether the cat carries one copy of the gene (a heterozygote) or two copies of the gene (a homozygote).

Should my cats be tested for HCM and how often should they be tested?

In clinical practice, the most common patients tested for HCM with echocardiography are cats with suggestive clinical signs of heart disease, such as a heart murmur. Testing cats used in a pedigreed breeding program is a more difficult endeavor. Echocardiography is not a perfect tool for diagnosis of HCM – some affected individuals will escape detection and access to good quality ultrasound services may be difficult and expensive for some breeders. At the very least, breeding cats should be ausculted (examined by a vet with a stethoscope) for heart murmurs or arrhythmias once yearly. Any cat with an abnormality should have an echocardiogram. A significant percentage of cats with HCM will not have a heart murmur, however.

Since HCM can occur at any age, a single normal echocardiogram does not guarantee a cat is free of disease. Breeding cats should probably have an echocardiogram yearly during their breeding years. Examining retired cats periodically is also advantageous as this may allow the identification of affected cats that have offspring in a breeding program.

A Maine Coon cat that tests negative for the cMyBP-C mutation is not guaranteed to be free of HCM, for it is not known if other mutations causing HCM are present in this breed. Ideally, cats that test negative for the cMyBP-C mutation should still undergo echocardiogram screening. Cats that test positive for the disease should not be bred. They will most likely develop the disease at some time during their life although it may be too mild to detect even on an echocardiogram.

At what age should a cat be tested for HCM?

HCM can affect cats at any age. It has been seen in kittens only a few months of age and in cats over the age of 10. In Maine Coons, most affected male cats have evidence of disease by 2 years of age, and most affected females have evidence of disease by 3 years of age although instances have been documented where the disease has not shown up until much later. Ragdolls with severe disease seem to develop it earlier in life, often at under 1 year of age. Guidelines for other breeds have not yet been developed. It is therefore hard to recommend a specific age to start testing. It may make sense to screen most breeding cats with an echocardiogram for the first time around the age of 2 years. Maine Coons may be tested for the cMyBP-C mutation as kittens.

What do I do if my cat is diagnosed with HCM?

The cat should be removed from the breeding program and all offspring should be watched closely for the development of HCM. Statistically, 50% of the cat’s offspring would be expected to have the genetic mutation that causes HCM if one parent was a heterozygote. However, the most prudent approach may be not to use any of the offspring in a breeding program. The offspring of Maine Coon cats with the cMyBP-C mutation should be individually tested to determine their status.

The parents of an affected cat should also be examined with echocardiography (and tested for the cMyBP-C if a Maine Coon), as one of them likely carries a gene mutation for HCM. In some cases, identification of the affected parent may be difficult, especially if the disease is mild. In these cases, the most prudent approach may be to remove both parents from the breeding program. It is possible for a cat to develop a spontaneous mutation that causes HCM during embryonic development but this is an unlikely cause in a breed known to have the problem.

All breeders that are using cats related to an affected cat should be notified that a cat has been diagnosed with HCM. Similarly, pet owners should be notified that a relative has been diagnosed with the disease. Echocardiographic examination (and genetic testing if a Maine Coon) of cats related to the affected cat should be performed.

Will we ever eliminate HCM from my breed?

The tools we currently have to diagnose HCM (i.e., echocardiography and necropsy) are not perfect and will not allow us to totally eliminate this disease. However, echocardiographic screening will be able to reduce the incidence of HCM within a breed if enough breeders are involved.

The identification of the cMyBP-C mutation in the Maine Coon and the development of a genetic test provide breeders with a new tool to reduce the prevalence of or theoretically eliminate the mutation within this breed by not breeding affected cats. Breeders should use all the information they can gather about HCM in family lines, including pedigree analysis based on accurate identification of affected cats.

Any cat that dies suddenly or dies from HCM should have a necropsy (i.e., post mortem examination). Most cats with HCM will have a heart that weighs more than 20 grams and most cats with severe HCM will have a heart that weighs more than 30 grams. Myocardial fiber disarray, the hallmark microscopic heart muscle abnormality seen in humans with familial HCM is seen in all Maine Coon cats with HCM. Unfortunately, most veterinary pathologists are not trained to recognize this lesion.

In the long term, we will need a genetic test for HCM in each breed. A genetic test allows us to identify affected cats before they were bred and do so accurately. Since the disease is inherited as an autosomal dominant trait, once a mutation is identified, if all breeders cooperated by testing their breeding cats for the mutation the disease could be eliminated from the breed within several generations. However, the money and resources necessary to identify the gene or genes and to develop a genetic test for each breed are scarce in veterinary medicine. Breeders and cat fanciers can help by supporting research through organizations such as the Ricky Fund established by the Winn Feline Foundation.

Can two normal parents produce a kitten with HCM?

Since HCM is known to be an autosomal dominant trait in the breeds where the inheritance is known, each affected cat must have one affected parent. However, there are possible situations in which an affected cat may come from two apparently normal parents.

The first possibility is that one of the parents has been misdiagnosed. This can happen due to inexperience of the ultrasonographer or poor quality equipment. It can also happen if a cat’s status is decided on the basis of only one or two ultrasounds early in life. Since HCM can develop at any age, a cat that is normal on ultrasound one year could still have HCM and show signs later in life.

Since the trait has variable expression, not every affected cat will have echocardiographic evidence of HCM. It is therefore possible for a cat to test negative for HCM on ultrasound, and yet still carry a genetic mutation and pass it to offspring.

Finally, it is possible for spontaneous mutations to occur in cats from normal parents. These cats may then pass on their mutation to offspring. We do not know how often spontaneous mutations causing HCM occur in cats. Statistically, spontaneous mutations are more likely to occur in random bred cats than in pedigreed cats.

What does “HCM free cattery” mean?

There is no universally agreed upon definition of an HCM free cattery. The terminology is currently unclear, as different breeders mean different things when they use this term. Ideally, each breed should develop a specific definition and guidelines for use of this designation for catteries.

Most people are surprised that Sphynx cats actually have more grooming responsibility than cats with hair. They don’t have to be brushed obviously, but they do need weekly baths. Most Sphynx are used to being bathed so they tend to tolerate their weekly baths well.

How you bathe your cat depends on your preference. Some people like to fill up the sink/tub with water and others prefer to use the hand nozzle to the sink. The water temperature should be warm but not too hot. I get their bodies a little wet and then put some shampoo on their back and starting working up a good lather. Wash their bodies well with the wash cloth but don’t rub too hard since Sphynx have sensitive skin. I use baby shampoo for their bodies which seems to work well and doesn’t burn if it gets in their eyes. Make sure to wash their whole bodies, including their rear end and tail. Pay close attention to their toes and nail beds, where oils can accummulate and need to be removed. After rinsing the cat, I wrap them in a warm towel then start cleaning their ears while they are nice and warm. Wrapping them up like a little burrito and setting them on the counter works well!

Most cats dont mind their ears getting cleaned and it only takes a few minutes. I use Nutra-vet ear cleanse for cats but have used others that work just as well. Use the washcloth and ear cleaner to gently clean the inside of the ear. If needed you can use q-tips to get into the crevices of the ear – just don’t go too deep. You can cause damage to the cat’s ear canal. After cleaning the ears, I check the cat’s nails to see if they need to be trimmed. I generally trim them twice a month. Just clip the very tip of the nail off. Their nails are clear – you should be able to see the pulp inside. Only cut the clear portion!

After all that is done, bath time is over and you have a squeaky clean Sphynx! Repeat weekly or as needed!

That is one of the first questions I am asked when someone is looking for a Sphynx kitten and has known cat allergies. To answer that question, you must first understand the no breed of cat is completely non-allergenic or “cat allergy free”. Hypoallergenic means low allergen, and refers to cats that typically produce fewer allergens than “regular” cats. The protein (Fel D1) is the allergen in a cat’s saliva that causes problems for allergy sufferers. Once the cat licks its fur, the allergen is transferred to the fur of the cat, which is then shed all over your furniture, carpet, clothing etc and causes problems for people with cat allergies. Sphynx cats still have the protein present in their saliva, and do still lick themselves to groom, but without their hair shedding all over the house, they offer an alternative that some cat lovers can live with.

My husband and two daughters are allergic to cats in the traditional sense – if we visit a friend that has cats inside the home, within a few minutes of the visit, their eyes begin to water and the sneezing begins. However, we have had our Sphynx cats for 6 years now and all are able to handle the cats with no issue. At one time we have had as many as 20 cats and kittens in the house! Friends have come to our home and have held our cats who have never been able to be near cats before. We have found this to be true time and time again. If you are allergic to cats but would like to meet our Sphynx to see if the breed is right for you, plan to stay for a few hours and really spend time with the cats.

Once you have adopted your Sphynx cat, there are steps you can take to minimize allergens. They are:

Frequent bathing. Sphynx cats should be bathed once a week to keep their skin clean and remove oils that can build up. This also includes cleaning their toenails and ears.

Wash cat toys and bedding frequently.

Wash your hands and face after touching the cat. Remembering this simple step can make a big difference for the typical cat allergy sufferer.

Most people with typical cat allergies are not bothered by the Sphynx breed, but do your homework if you are considering a Sphynx. They are great companions and the best part of owning a “hairless” cat is no shedding!

The Sphynx cat is a very unusual and rare breed. They are often referred to as the Canadian Hairless Cat. They have very little fur and lack of whiskers. What fur some Sphynx cats may have will appear as a very fine down. The skin of the Sphynx can exhibit colors and markings and they have sometime been mistaken for Chihuahuas.

The face of the Sphynx is quite expressive and dominated by its large eyes and ears. Naturally occurring skin oils means that the Sphynx needs occasional bath. This is an intelligent cat that is devoted to favored humans. Affectionate and playful, this unique breed can make a great companion cat.

Sphynx Cat History

The Sphynx cat originated from a natural mutation in a kitten born in Toronto, Canada in 1966. The Cat Fanciers Association included this breed in the miscellaneous category in February 1998 and championship show recognition in 2002.

The ancestor of all domestic cats is the African Wildcat, the genus Felis Lybica. This genus is comprised of smaller cats. Cats are thought to have been domesticated with the advent of farming and the storage of grain. The grain attracted rats and other vermin which naturally attracted wild cats. As time evolved, certain of these cats were domesticated for the mutual benefit of both cat and man. The African Wildcat has certain features which is obvious in the housecat of today.

Feline Health Considerations

Cats who reside in the house should generally visit the veterinarian yearly, unless health problems are evident. Cats who enjoy the outdoors may need to see the vet as many as four times a year. When you take your cat to the vet, be sure to bring along a fresh stool sample so the vet can do a fecal exam to check for internal parasites such as tapeworm, round worm, whip worms and hook worms. The vet will also check for external parasites such as fleas, ticks and ear mites.

Any vet check should include a dental examination and a cleaning if necessary. Cats who are eight years of age or older are considered geriatric and additional blood and urine tests may be necessary to screen for any health problems. At about six months of age, the kitten should also be examined for sexual maturity and decisions about birth control should be made.

Behavioral Traits

Gets along with other pets
They like to cuddle and snuggle
Very friendly and outgoing
They like to be the center of attention

Sphynx Cat Registries and Clubs

Sphynx and Rex Association
The Rex and Sphynx Club of Denmark
Cat Fanciers Association CFA
International Cat Association TICA
The Traditional Cat Association TCA
Canadian Cat Association CCA
The Australian Cat Federation
The American Association of Cat Enthusiasts AACE
American Cat Fanciers Association ACFA
United Feline Organization UFO
Cats United International

Kitten Care

Sphynx kittens can be hard to come by and it is not uncommon for buyers to be placed on a waiting list. Unlike puppies, kittens should not be separated from their mother until twelve to sixteen weeks of age. Some very important developmental stages occur during this period including emotional, mental and health. Curtailing this development may lead to any number of medical and behavioral problems.

Kittens that are separated from their mother at too young an age often fail to gain weight fast enough, have immune system problems because they have not had enough mothers milk. The may also develop eating and eliminating problems, and can have problems socializing with other cats and with people.

Every cat and kitten is an individual so not everything in this information may be correct for your cat or kitten. This information is meant as a good faith guideline only.